This invention concerns improvements to fluid connectors for connecting grids of heat exchangers and improvements to methods of making fluid connectors. In particular, but not exclusively, the invention relates to bosses for a connecting grid used within a plate heat exchanger.
It is known to use bosses for providing a fluid connection to sections of a plate pack of a heat exchanger separated by a connecting grid. These known bosses have a high manufacturing cost. A prior art boss is shown in FIG. 19 of the drawings.
The boss (1900) is usually manufactured by sand or investment casting and subsequently machined to quite high tolerances to ensure that it will fit in a connecting grid. Where it is important to ensure a sanitary surface, i.e. where milk or other food product is to be passed through the heat exchanger, grinding and polishing of the boss is necessary.
The boss (1900) is provided with an opening (1905) for connecting to a heat exchanger and an external opening (1904) having a fitting (1902) for connecting to the user's pipework. The fitting (1902) can be welded onto a branch (1903) of the boss (1900). A seal ring (port ring) or elastomeric gasket is used between the opening (1905) of the boss (1900) and a heat transfer plate of the heat exchanger to seal the boss (1900) against the heat transfer plates. The port ring sits within a groove machined into the boss (1900).
Assembly of this boss (1900) to a connecting grid is achieved by locating the boss (1900) over a dowel protruding from the connecting grid and securing the boss (1900) by a short hex head screw.